Applied Mechanics and Materials Vols. 97-98

Abstract: With the influence of many factors such as policy, economy and natural environment, large-scale coal enterprises face kinds of risk. The way how to identify and control the risk is becoming the focus of them. From the angle of supply chain link, with the method of questionnaire and on-the-spot investigation, twenty kinds of risk factors are identified and determined. A set of index system of coal supply chain evaluation is established. And the SVM model is used to evaluate the harm degree of risk factors. Risk control solutions-“three-level inventory” risk pre-warning and emergency response mechanism is formulated. The index of evaluation roundly considers risk factors in every link of supply chain. The “three-degree inventory” risk pre-warning and emergency treatments mechanism can provide effective reference for decision-makers.

Abstract: This paper studies the time matter in distribution center’s service level, states a model’s preconditions and constructs a location model of multi-level disribution center which concerns the time matter. In solution, it studies the advantages and disadvantages of genetic algorithm, proposes a mixed strategy, designs the HGA program and studies the application of HGA in the location model of distribution center. In the end , it shows the practicality and correctness the proposed methods and models by the application in the practical case.

Abstract: Container handling in the ports of the Bohai Bay region is analyzed from the perspective of the competitiveness of the Port of Qingdao. The Analytic Hierarchy Process (AHP) method is applied to this problem based on the main factors affecting the competitiveness of container handling. The results of the analysis suggest that the Port of Qingdao possesses both current and potential future competitive advantage. The paper concludes with some strategic measures and suggestions for boosting the competitiveness of the Port of Qingdao.

Abstract: The origin, the composition, the function, the application and the developing trend of the Internet of Things (IOT) were reviewed. The application of internet of things would greatly improve the information technology in logistics. The internet of things supported by RFID and sensor technology has been applied in the area of logistics. A framework of three technical systems of sensing, communication and network, and intelligence has been established. The present technology of internet of things in logistics of forest industry was analyzed. The application cases of the internet of things in timber storage, wood transportation and logistics of forestry biomass materials were shown with their system composition, management function and development.

Abstract: Bus networks occupy less space in city streets, and compared to other kinds of public transportation, need less investment cost. An accurate bus operation schedule which considers actual arriving and departure time is essential for bus companies, due to high passenger demand. In real-world cases, there are daily differences in the frequency of bus dispatch from the terminal, and headway of buses between each bus bay along their route, depending on peak hour traffic and resulting congestion. In this research we studied effective parameters for preparation of proper bus operation scheduling. Measures are essential to ensure that buses receive priority over other traffic, if they are to be attractive to passengers. Finally, we suggest some solutions for lessening interval time in headway and frequency scheduling for bus services. Data obtained from an actual bus operation in the city of Tehran in Iran was used in this study.

Abstract: This paper establishes the differential equation model and simulink simulation model of Electric Power Steering (EPS). After determining the structure of the control system, closed-loop control of given signal filtering and steering dish corner feedback signals was used respectively. The simulation shows that control strategy reduced the tracking error and the system dynamic response characteristics were good.

Abstract: Stochastic theory and probabilistic perturbation are introduced in this paper. According to the instantaneous speed and maximum braking force, the vehicle braking performence evaulation is established, in which the uncertainty of stochastic parameters are analysed. Compared with that of Monte-Carlo’s, the result shows that the accuracy of the braking performance is improved.

Abstract: A 3-DOF multi-axle steering vehicle model were established using Lagrangian analysis method, including steering system stiffness, cornering stiffness and power steering system. The vehicle model is verified correctly and universally by using front wheels steering vehicle model. Based on the vehicle model, the steady circling parameters of multi-axle steering vehicle are presented. The effects of vehicle physical parameters on the steering characteristics of multi-axle steering vehicle are analyzed. To further demonstrate the correctness of multi-axle steering vehicle model, a three-axle steering vehicle model were built by ADAMS software. It is a theoretical basis for the design of multi-axle steering vehicle and the evaluation of steering characteristics.

Abstract: The sub-frame of 2500HP fracturing truck is an important component, which connects to chassis with the vehicle equipment. Because the sub-frame bears tension, torsion and bending loads, enough rigidity and intensity are necessary for chassis. Based on the Pro/E software, the 3-D model of frame and sub-frame was constructed. Using topology optimization method, layout of the sub-frame was determined and location of crossbeams was arranged. Meanwhile, number and location of the connectors between main frame and sub-frame was analyzed, analysis result shows that carrying capacity of chassis can be enhanced without increasing connectors number of main frame and sub-frame. Some available reference can be provided for chassis manufacture

Abstract: With the popularity of automobile, the safety test of automotive part becomes more and more important. As one of important indexes, the stiffness can judge the safety of automobile. The slope of initial point on load-deflection curve was considered as the evaluation criterion of stiffness for panel parts, and the stiffness instrument was designed based on this working principle. The bulge-tensile stiffness of automotive panel was tested by this instrument, and the instrument could meet the requirement of measuring stiffness by analyzing experiment dates and calculating the measurement accuracy of test points.